We present a new hybrid method for dilute gas flows that heterogeneously couples a continuumfluid
description to the direct simulation Monte Carlo (DSMC) method. A continuum-fluid model is applied
across the entire domain, while DSMC is applied in spatially-distributed micro regions. Using a field-wise
coupling approach, DSMC sub-domains of any size can be placed at any location. The sub-domain
arrangement can therefore be adjusted for each problem to capture non-equilibrium behaviour both close to
bounding walls and in the bulk. We demonstrate our method on a test case of high-speed micro Couette flow.
With large differences in wall velocity, significant viscous heating is present, and so our coupling considers
the transfer of both momentum and heat. Our hybrid results are validated against a pure DSMC simulation,
and the results show that the method can deal with missing boundary and constitutive information.

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This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.